The electrical panel breaker won't trip in your situation as the GFCI outlet trips instead. Remember that your GFCI outlet can protect downstream outlets. i.e, power goes from breaker in panel to GFCI outlet in master bath, from the master bath it goes to the hall bath, from the hall bath it goes to the outlets on the outside of the house. In this example, The only one with a reset button will be the GFCI outlet in the master bath, but NONE of the other outlets will have power until that master bath GFCI is reset. AND, if there's more than one GFCI outlet in the circuit, such as a second one in the hall bath, ALL of the GFCI reset buttons on that circuit need to be reset before you get power back. If it was working fine before, it's likely still working fine, you just have to find the GFCI outlets and ensure all of them are reset. Check all the kitchen outlets, bathroom outlets, garage outlets (look behind the refrigerator and any shelving) and exterior outlets, crawl space outlets, basement outlets, etc to see if any of them are a GFCI outlet, reset them and ensure there's power to them (plug something into them). Sometimes this can be a real hunt. I doubt you need to replace anything. You just need to find the tripped GFCI Outlet and reset it.